Helical cutting mechanism for harvesters



Filed March 31, 1951 I s. F. PASTURCZAK 2,654,208

Oct. 6, 1953 I HELIC'AL'CUTTING MECHANISM FOR HARVESTERS 3 Sheets-Sheetl FIG. l

V EN TOR.

11v STANLEY EPASTURCZ S. F. PASTURCZAK, HELICAL. CUTTING MECHANISM FORHARVESTERS Filed March 51, 1951 s' Sheets-Sheet 2 INVENTOR: STANLEY F.PASTURCZ 1953 I s. F. PASTURCZAK 2,654,203

HELICAL CUTTING MECHANISM FOR HARVESTERS Filed March 31, 1951 sSheets-Sheet 5 FIG? INVENTOR. STANLEY F. PASTURCZA Patented Oct. 6, 1953HELICAL CUTTING MECHANISM FOR HABVESTERS Stanley F. Pasturczak, EastMoline, Ill., assignor to Deere & Company, Moline, III., a corporationof Illinois Application March 31, 1951, Serial No. 218,576

2 Claims. 1

This invention relates to a crop harvester and more particularly toimproved cutting mechanism therefore. i

The conventional crop harvester, as typified by a mower or combine,comprises cutting mechanism including a sickle bar disposed transverseto the line of travel and having a plurality of forwardly projectingsickle guards, in addition to which a reciprocating knife is carried bythe sickle bar for movement back and forth lengthwise of the bar. Thisconstruction has withstood many attempts to replace it, in spite of itsinherent disadvantages. Among these disadvantages are relatively highcost, excessive vibration in use, frequent breakage of the parts,replacement or sharpening of the knife, and other malfunctioninginherent in the basic structure.

According to the present invention, it is an object to provide animproved cutting mechanism in which a rotating cutter is substituted forthe reciprocating cutter. The rotating cutter is carried in a fixed partof novel design. Specifically, the fixed part or outer part of thecutting mechanism comprises an elongated member of uniform cross sectionwound as a hollow helix having a uniform inside diameter providing aninternal cutting edge. The rotating part comprises a smaller helix ofuniform outside diameter arranged in homocentric relation with the outerpart and carried thereby for rotation relative thereto so that the innercutting edge of the outer part and the outer cutting edge of the innersmaller part cooperate to out crops such as standing grain or grasses.It is a further important object of the invention to provide the outerhelix with an internal bearing surface in addition to the internalhelical cutting edge. This bearing surface supports the inner helix. Ina preferred form of the invention, the inner helix is formed of anelongated member wound in helical form and presenting an outer helicalsurface delineated by a pair of helical edges, either of which may beused as a cutting edge, since the inner helix can be reversed from endto end. It is a further object to provide the outer helix of such crosssectional stock that a helical outer edge is provided that acts in theform of a divider to function very much in the manner of theconventional mower guard in separating and guiding the standing grain orgrasses. Still another object is to provide a cutting mechanism that maybe readily used in mowers or combines of existing construction withoutmaterially modifying the basic design of such conventional structure.

The foregoing and other important objects and desirable featuresinherent in and encompassed by the invention will become apparent as acomplete disclosure of preferred embodiments of the invention is made inthe following detailed description and accompanying sheets of drawingsin which Figure 1 is a fragmentary perspective view of a forward portionof a conventional combine equipped with the improved cutting mechanism;

Figure 2 is an enlarged front elevational view of the cutting mechanism,portions of the mechanism being omitted to permit the use of a largerscale in the drawings;

Figure 3 is an enlarged fragmentary elevational view on the same scaleas Figure 2 of a portion of the internal cutter;

Figure 4: is a transverse sectional view taken on the line 4-4 of Figure2;

Figure 5 is atransverse sectional view taken on the line 5-5 of Figure2;

Figure 6 is an enlarged sectional view taken on the line 6-6 of Figure3;

Figure '7 is a detail perspective view of a supplemental guard ordivider used in conjunction with the improved cutting mechanism;

Figure 8 is a fragmentary view of part of a modified form of outerhelica1 member in which the cutting edges are serrated; and

Figure 9 is a view similar to Figure 3 but showing a modified form ofinner member in which The combine illustrated is of the self-propelled.

type having a main body I0 carried on a pair of traction wheels I2 andI4. The main body carries ahead of it a platform structure l6 which istransverse to the line of travel. This platform structure has at aforward or leading portion thereof the improved cutting mechanism,designated generally by the numeral l8. A conventional reel 20 may beused in cooperation with the cutting mechanism M3 to deliver the cutgrain or grasses rearwardly into an auger trough 22 in which an auger 24operates to move the cut grain or grasses transversely and thenrearwardly to threshing mechanism (not. shown) associated with thecombine in the usual manner. A represent'ative complete. disclosure willbe found in U. Patent2,5 29,'180. V

. The cutting mechanism has at one end thereof a second or inner means38. The outer meansispreferably in the form of an elongated membemofuniform triangular section as best shown attlihe left-hand end of Figure2. ,Ilie triangulansection thus has three sides 'fllffliand legthezeide40 forming the base and'the sides 42 and "M extending therefrom andconverging to an apex 46. The apex need not beisharpsbutemaysbe slightlyrounded or in the form of aneggiveias shown.

The means or first member 36 is wound as a helix; as-shown, that'has1a'1ho1lowcenterof Y uniform inside diameter. "Thebase or side Ml-fthe triangular section-thus epresents to the inside" of the helixrahelical inner surface fl. 'Ihaside-" i2 adjoins or forms a junction atfifl with the: base es and a similar relationship exists at 52 betweenthe bassist and the side- M. *In its helical form, these two "junctions1 form a paivof --continuous helical -edges 54: a-nd 5fipwhich are;parallel and "which delineatewoppositeedges ormargins ofthe innerhelical-surface 48. Theapex-"flBofthe tri- 'angularsection"becomesan-"outer edge=53, giving the, helical member 35 a uniform outsidediameter from end; to end.

The platform structure it 'comprises framework includingatransverseiorward member B8 in the form-ofa rearwardlyfacing angle(Figures 4 and5). ,To'theforward-fiangeli2-of the transverse member 60-is secured; a second transverse member or supporttdrr-theform o-afer--wardly -facing channel havingfllp er and' lower flanges S6 and 68.These-flanges may'ibe notched aixintervalstd'receivemxiaillyspacedportions of the helical member 36;-which portions are welded to theflanges-GB-and B8-respecibively-at Warrd 12. :From the description-thusiar, it will be seen that the means 'or memberi 6 -replacesithe-conventionaLsickle 'bar and guard. *Because' ofithe triangular sect-ion-of-the"member 336, the "outer helical edge 5B-serves-as "divideror-guide means Nfor guiding the standing;grainor grassesintov the spacesbetween-the'secticnspfthe helix. To-further augmentthe"GfiiGlGIlgYQfjthE cutting-mechanism, .there may be;proYidedTa"plura-lity of -divideracnly'one.ofwhich is-shown-atfl F ig-'ure2. This-dividerisshown alsojn Figure 4 and is shown by itselfin"Figure"'7. 'The divider extends forwardly in the formbirafingeranihas.a curved recess 16 jformed on-part-of'the basic helix; of. the member36' so as; to receive a lower portion of the member :36 as suggestediniFigures "2 and 4. 'Ihe.dividerhas a pa ir of attaching earsTB and 80aperturedre spectively at 82 and "84 to provide for .attachmentofthejdividertto thejfront face of the transverse member 62, as bybo1ts;36\ and 88 '(Figurem g The second. mea sor; inner member'all islike- ..wiseiormed from an elongated, member wound as a smaller helixhaving a ,uniform outsidegdiam- Heterjbut slightlygorjtolerably lessthan the. unij form insidejdiameter. .of the inner helical surface .'48of the means .ormemberifi. .Asbest shown in F gure 6, the member 38is.,l r.6.ferahly of. uniform cross section having a plurality. cflanularly re- .latedlsides 90,, 92,l94eand;9fi. TWhenthe. member is woundinto helical formfthe side'Sll is outer-' most and resents a helicalouter surface 98. The sides 92 and 96 present radially inwardly directedhelical surfaces I00 and 102. These sides respectively adjoin the side90 at corners or junctions I04 and I06. These corners presentheliealouteredges I08 and H0 respectively when rthe; memberwulds woundinl helie'aliorm.

The helical inner surface 48 of the outer helix 3B is axially directedand the two helical surfaces *presented by the sides 42 and 44 or thetriangular rsecticnohthevouter member 36 are radially out- :urandlydirected. The outer surface 93 presented ,by the side,90 of the innerhelix is also axially {directedand extends between the helical edges 51'04 and; H16. As.best shown in Figures 2 and 6, the surface 98 isconcave between these two sedgesxithusiaccentuating the edges so thatthese edges .provide cutting edges selectively cooperative with the edge56 of the outer helix 36, which edge 56 is likewise a cutting edge.

The-pitch oi the outer helixis preferably "-un'i-form,-as-is the-pitchof the inner -hel-ix'i38; although, it is preferred that the pit'ches of't-he --two-be-difierent. The relationship here=shown is 'such that thep'itch oi the inner'helix is "(in inches) "1.75 and the pitchofthe-outer helixis "2.00. Thus,"the pitch ofthe inner helix is smallerthan that of the outer helix. Inasmuch as the inner helix is supportedor journaled by the outer -helix*'-f0r rotation relative thereto, thedifference -in--pith prevents any-portionof"the-inner helix fromdropping 011b of supporting relationship to the outer 'helix. Thisis'particularly important -when it -is considered that the cuttingmechanismhasconsiderable'length, which :may be from anywhere from'fi t0-l6 -feet,for example.

As stated above, "the cutting mechanism is --driv-en-* by the: 'shaft'Z-S. --Speci'fically; this may be --accomplished by providing externalthreads at H 2 on the shaft 26 which --matewith internal threads (not'shown but suggested) at-=one end of the 'innerhelix 38. The-shaft-Ztmay be carried *inwa suitable thrust bearing I M carried in a side wa'llportion l l 6-of theplatfor-m structure 1 6.

:Inoperation, th combine 'proceeds forwardly over, thefieldandthestanding grain or grasses is directed into the cutting 'mechanismbecause of ftheapexe'dgeES-onthe outer helix iifi. The crop -isvcausedto enterthe spaces between the helical 5O 'portions'cf the helices 35and '38 where it is cut by the cooperating-cutting edges-- HlB and 55.This "W'ill-beapparent' from an examination of Figure'Z.

The inner helix S8 rotates-in the-direction ofthe arrow A shown inFigures 2, 4 -and '5.

=Since'the helix38 is uniform, as is the helix '55 =3,-the' former maybechanged from end toend "and utilized in such manner that the edge Ila]becomes-acutting edgecooperative with the cut- --ting edge-fifi'on'theouterhelix 36. This Be distinct advantage, because the inner helixpresents 60 "alternate-cutting edges andfibeeauseit-may be"inexpensively manufactured; both-edges may be -'usedan'd-the -memberdiscarded and rep-laced -w-ith a -new one of similar design.

In the modified forms of the invention shown in Figures-8 and 9,thefundamental design of'the "twohelices is followed. Therefore, thesame reference characters, followed bythe exponent a, will be'used. "Theonly difference between the two is-that'thetwo edges-5 la and 560, maybe -serrate'dor otherwise roughened as shown, whichi'lesign'maybedesirable in certain crop conditions. "The-inner helix.38ais modified in the same mannen-the cutting edges HEM-and H'Ga beingserrated. as illustrated.

"Various subsidiary featuresof the invention not specifically enumeratedherein will undoubtedly occur to those versed in the art, as likewisewill various modifications and alterations in the preferred designsillustrated, all of which may be achieved without departing from thespirit and scope of the invention as defined in the appended claims.

What is claimed is:

1. Cutting mechanism, comprising: a fixed support; a first elongatedmember of uniform crosssection wound as a hollow helix of uniform pitchpresenting a helical, internal bearing surface of uniform diameter, saidsurface having one marginal edge thereof formed as a coextensive helicalcutting edge; means rigidly securing said first member at axially spacedportions thereof to the support; a second elongated member wound as asmaller helix of uniform pitch and having an external helical bearingsurface of uniform diameter but tolerably smaller than the diameter ofthe aforesaid internal bearing surface; said members beinghomocentrically arranged with the second member inside and rotatablerelative to the first member, said bearing portion on the second memberriding on the internal bearing surface of the first member; said bearingportion on the second member having one marginal edge thereof formed asa coextensive helical cutting edge cooperative with the first membercutting edge; the ratio of the pitch of the first helix to the diameterof the internal bearing surface being in the order of between 1:1 and2:1, and the pitch of the second helix exceeding that of said firsthelix.

2. The invention defined in claim 1, in which: the cross-section of thefirst member is substantially triangular with the base of saidtriangular section toward the internal bearing surface and the sides ofsaid triangular section converging radially outwardly to an apex, givingsaid first member an outer helical edge serving as a crop divider.

STANLEY F. PAST'URCZAK.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 17,739 Irwin July 7, 1857 23,552 Colborn Apr. 12, 1859 227,950Beekman May 25, 1880 957,468 Lynch May 10, 1910 1,231,174 Koons June 26,1917 2,309,635 Edwards Feb. 2, 1943

